Herschel and Planck launch update

Roll out of Ariane 5

2 April 2009

The verification of operations procedures for Herschel and Planck at ESA’s European Space Operations Centre (ESOC) has now positively concluded. However, during final checks on the spacecraft, concerns have arisen and a short delay is proposed in order to allow ESA and Arianespace to carry out a final and independent check of the safety margins. Therefore, the final decision on the date of the Herschel and Planck launch will be postponed by a few days.

The Herschel telescope mirror, the largest ever to be launched in space, is a novel and advanced concept using 12 silicon carbide petals brazed together into a single piece; it is one of the major technological highlights of the mission. The complexity of the structure and its uniqueness means great care must be taken to ensure that stresses exerted on it during launch are well understood.

Over the next few days, a panel of independent experts led by the ESA Inspector General and Arianespace will carry out a final cross-check of the documentation to demonstrate that the required safety margins for the telescope are met.

The new launch date will be defined shortly.

The Herschel and Planck satellites, currently at Europe’s Spaceport in French Guiana, are on standby in perfect condition. Engineers are awaiting the new launch date in order to resume the final preparations for launch. These include the fuelling of the two satellites and the filling of the Herschel cryostat with helium.